Abstract: The dipole-resonator resistive absorber is a metamaterial absorber operating in the microwave regime. A single unit of the dipole-resonator resistive absorber includes a first rectangular conductive ring having a pair of first resistors mounted thereon and in electrical communication therewith, and a plurality of parallel linear arrays of second rectangular conductive rings, where each of the second rectangular conductive rings has a pair of second resistors mounted thereon and in electrical communication therewith. The first rectangular conductive ring is mounted above the plurality of parallel linear arrays of the second rectangular conductive rings, and this structure is backed by an electrically conductive layer. The single unit dipole-resonator resistive absorber may be expanded into an arrayed structure, forming a polarization-independent dipole-resonator resistive absorber.

Abstract: A high capacity nanoparticle-based covert barcode system relies on an entirely optical readout for detection. The system includes a panel of phase change nanoparticles with sharp and discrete melting peaks; readout is based on heating with an infrared source and detection using an infrared imager, and detection of their phase transition temperatures and positions. A readily detectable and sudden change in temperature occurs at the phase transition during a heating or cooling process, and can be used to indicate the identity of nanoparticles.